Unable to add an element to an arraylist using extended class

Dear all,
I am facing a problem of using an class which is a sub class of another. Using in the sense, putting the attributes of the extended class into the arraylist that initially uses the original class for the main class. I hope to understand more about this problem. Here are the codes..

I am facing a problem of using an class which is a sub class of another.

I am assuming that the problem that you are facing, is that it won't compile? As neither of the two classes have constructors that has the same name as the class. (and if they are methods, then they don't have a return type).